From: Marek Vasut marex@denx.de
[ Upstream commit 64a632da538a6827fad0ea461925cedb9899ebe2 ]
The phy_reset_after_clk_enable() is always called with ndev->phydev, however that pointer may be NULL even though the PHY device instance already exists and is sufficient to perform the PHY reset.
This condition happens in fec_open(), where the clock must be enabled first, then the PHY must be reset, and then the PHY IDs can be read out of the PHY.
If the PHY still is not bound to the MAC, but there is OF PHY node and a matching PHY device instance already, use the OF PHY node to obtain the PHY device instance, and then use that PHY device instance when triggering the PHY reset.
Fixes: 1b0a83ac04e3 ("net: fec: add phy_reset_after_clk_enable() support") Signed-off-by: Marek Vasut marex@denx.de Cc: Christoph Niedermaier cniedermaier@dh-electronics.com Cc: David S. Miller davem@davemloft.net Cc: NXP Linux Team linux-imx@nxp.com Cc: Richard Leitner richard.leitner@skidata.com Cc: Shawn Guo shawnguo@kernel.org Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/ethernet/freescale/fec_main.c | 25 +++++++++++++++++++++-- 1 file changed, 23 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c index 3b6da228140e..a81f5ced39f1 100644 --- a/drivers/net/ethernet/freescale/fec_main.c +++ b/drivers/net/ethernet/freescale/fec_main.c @@ -1897,6 +1897,27 @@ static int fec_enet_mdio_write(struct mii_bus *bus, int mii_id, int regnum, return ret; }
+static void fec_enet_phy_reset_after_clk_enable(struct net_device *ndev) +{ + struct fec_enet_private *fep = netdev_priv(ndev); + struct phy_device *phy_dev = ndev->phydev; + + if (phy_dev) { + phy_reset_after_clk_enable(phy_dev); + } else if (fep->phy_node) { + /* + * If the PHY still is not bound to the MAC, but there is + * OF PHY node and a matching PHY device instance already, + * use the OF PHY node to obtain the PHY device instance, + * and then use that PHY device instance when triggering + * the PHY reset. + */ + phy_dev = of_phy_find_device(fep->phy_node); + phy_reset_after_clk_enable(phy_dev); + put_device(&phy_dev->mdio.dev); + } +} + static int fec_enet_clk_enable(struct net_device *ndev, bool enable) { struct fec_enet_private *fep = netdev_priv(ndev); @@ -1923,7 +1944,7 @@ static int fec_enet_clk_enable(struct net_device *ndev, bool enable) if (ret) goto failed_clk_ref;
- phy_reset_after_clk_enable(ndev->phydev); + fec_enet_phy_reset_after_clk_enable(ndev); } else { clk_disable_unprepare(fep->clk_enet_out); if (fep->clk_ptp) { @@ -2938,7 +2959,7 @@ fec_enet_open(struct net_device *ndev) * phy_reset_after_clk_enable() before because the PHY wasn't probed. */ if (reset_again) - phy_reset_after_clk_enable(ndev->phydev); + fec_enet_phy_reset_after_clk_enable(ndev);
if (fep->quirks & FEC_QUIRK_ERR006687) imx6q_cpuidle_fec_irqs_used();